Exogenous salicylic acid reduces decay and preserves bioactive compounds in bell pepper during cold storage

Bell pepper is a valuable vegetable crop, but its postharvest quality is often limited by rapid deterioration and senescence. Salicylic acid (SA), a novel plant growth regulator, has gained significant attention for its ability to delay ripening and slow down senescence in various fruits and vegetables. This study evaluated the effect of SA treatment on the bioactive compounds, antioxidant activity and postharvest shelf life of bell peppers. The fruits were dipped in different SA concentrations (50, 100, 200 and 300 μM) for 15 min and then stored for 20 days at 10 ± 1°C temperature with 85-90% RH. Bell peppers treated with 200 μM SA showed a significant reduction in weight loss, respiration rate and malondialdehyde content while retaining higher firmness, total phenolics, flavonoids and ascorbic acid compared to untreated fruit. Additionally, it maintained higher DPPH radical scavenging activity, capsaicin and proline content throughout cold storage compared to the control. Notably, the 200 μM SA treatment extends the shelf-life of bell peppers up to 20 days without compromising sensory acceptability as against 10 days in control.